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Roche / Mabthera

Mabthera infusion contains the active ingredient rituximab, which is a type of medicine known as a monoclonal antibody. It works by attacking white blood cells called B cells. This action means it can be used to treat two different diseases: cancers of the lymphatic system known as non-Hodgkins lymphomas, and the inflammatory disease of the joints known as rheumatoid arthritis.

Lymphomas are cancers involving white blood cells called lymphocytes. Cancer occurs when these lymphocytes, for some reason, begin to multiply in an uncontrolled way. This can cause a lump or tumour in the lymph nodes. Lymphocytes are normally involved in fighting infection and they travel around the lymphatic system and the bloodstream to do this. If abnormal cancerous lymphocytes travel, the cancer can spread to other lymph nodes and other areas of the body.

Rituximab is used to treat non-Hodgkins lymphomas that involve a sub-group of lymphocytes called B lymphocytes. It works by attacking the abnormal B lymphocytes.

Rituximab works in a similar way to the natural antibodies produced by our immune system. Our natural antibodies recognise foreign invadors and bind to them, helping our immune systems to attack them and protect us from infections. Monoclonal antibodies like rituximab are made in laboratories. They are designed to attack particular body cells.

Rituximab specifically recognises and binds to a protein called CD20, which is found on the surface of cancerous B lymphocyte cells. This triggers the immune system to attack the cancerous cells, and can also sometimes cause the cells to destroy themselves. This is how how rituximab works in treating lymphoma.

This medicine will either be given on its own to treat lymphoma, or in combination with other chemotherapy medicines. If used on its own, it will usually be given once a week for four weeks. If used in combination with other chemotherapy, it will be given on the same day as the other medicines, which are usually given eight times at three week intervals. Courses may be repeated. If the cancer responds to the intial treatment, maintenance treatment may be given once every three months for up to two years.

Rituximab can also be used to treat severe forms of rheumatoid arthritis. This disease is known as an autoimmune disease, because the inflammation and damage to the joints results from overactivity in the immune system. B lymphocytes seem to play a key role in this process. Rituximab works in rheumatoid arthritis by attacking the B lymphoctyes in the same way as described above. This interrupts the process of inflammation and damage in the joints.

Rituximab will be given as two doses, two weeks apart for rhemuatoid arthritis. This course may be repeated after six to twelve months if your doctor feels it is necessary to control your symptoms.

Rituximab is given by a drip into a vein (intravenous infusion). Some people can have a severe allergic reaction to rituximab, so to reduce the chance of this the first drip will usually be given over a period of a few hours. You will also usually be given some painkillers, antihistamine and possibly steroids before the drip to help prevent a reaction.

What is it used for?
A type of cancer of the lymphatic system called follicular non-Hodgkins lymphoma (as a first-line treatment in combination with CVP chemotherapy). Follicular non-Hodgkins lymphoma that is resistant to chemotherapy or has relapsed following chemotherapy. A type of cancer of the lymphatic system called CD20 positive diffuse large B cell non-Hodgkin's lymphoma (in combination with CHOP chemotherapy). Severe active rheumatoid arthritis, in combination with another medicine called methotrexate, in adults whose arthritis has not responded well enough to treatment with disease modifiying antirheumatic drugs (DMARDs including infliximab, etanercept or adalimumab), or who cannot take these medicines due to side effects.